Yea see people i have heard are saying for gaming you could just use a single core processor like the AMD 3700+ or 4000+, but then others say that the Intel Dual-Core E4400 is like the number one gaming and multitasking CPU out there right now but youll have to spend the lil extra buck.

There will be a slight boost in performance for gaming with a dual core just due to the fact that one core can handle task bar apps., leaving the other core free to process the game for the most part, alone. If you dont really run other apps. in the background then go single, it would certainly be cheaper with not a huge loss in performance. If you got the money, 6700-4400 duo would be my choice, if not then amd is offering very good cards as well for a cheap price.